Many network users regularly transmit and/or receive messages over T1 carriers in the U.S. and Canada (1.544 Mbits/sec rate; required line impedance of 100 Ohms), over E1 carriers in Europe (2.048 Mbits/sec rate; required impedances of 75 Ohms or 120 Ohms), and over J1 carriers in Japan (1.544 Mbits/sec rate; required impedance of 100 Ohms). Presently, transmission and receipt of digital signals on a T1 line and on an E1 carrier, for example, require use of separate chips to compensate for different required impedances, different framing patterns, different bit rates and such. In the future, Digital Subscriber Lines (DSLs) will transmit digital signals at selected rates, such as Tn and En and Jn rates (n=1, 1C, 2, 3, 4, 4M . . . ), and will become important for heavy duty information transfer, such as multicast communication for various Internet Protocol ("IP") applications (voice band telephone, picturephone, combined voice-over-data transfer, video-on-demand, etc.).